Tin core processing of powder metallurgy Cu-Nb-Sn

Powder metallurgy processed CuNbSn superconducting wires were fabricated using different internal tin core geometries. Variations of the process included: 1) a single central tin core surrounded by a multifilamentary composite or by a multistran powder composite, and 2) bundled multistrand compacts, each containing a tin core. External Ta or Nb barriers were also incorporated in the wire. Nominal areal reductions of 10⁴to 10⁶were used. Overall critical current densities of 3 × 10⁴A/cm²at 14 tesla were achieved.